1. Field of the Invention
The invention relates to a cushion material fastening structure for an interior trim part, and in particular to a cushion material fastening structure that makes it possible to easily fasten the cushion material without requiring high accuracy in positioning and is therefore excellent in workability.
2. Description of the Related Art
A cushion material that has a certain function of sound insulation, shock absorption, etc. is provided on a back side of an interior trim part, such as a vehicle door trim, for example. Japanese Patent Application Publication No. 2003-81021 (JP-A-2003-81021) gives an example, in which holes or slits are provided in the cushion material and fastening protrusions on the interior trim part side are inserted into the holes or the slits, whereby the cushion material is fastened by the fastening protrusions or catching teeth provided on the fastening protrusions.
However, when the cushion material is fastened by providing the cushion material with the holes or the like and inserting the fastening protrusions on the interior trim part side into the holes, the fastening operation has to be performed after relative positioning between the cushion material and the interior trim part, and therefore, the workability is not satisfactory in some cases. In addition, because of the variations in the positions of the holes or the like, there is a possibility that the position of fastening of the cushion material to the interior trim part is deviated and looseness due to this positional deviation occurs.